Savannah Fanjul thinks about her step-sister Kayleigh Slusher, Monday February 3, 2014, as she sits on the steps at the memorial outside the apartment building in Napa, Calif. Three year old Kayleigh Slusher was found dead, Saturday in her bed. The mother Sara Krueger and her boyfriend Ryan Scott Warner have been arrested on suspicion of murder and assault in connection with the killing of Kayleigh.

Photo: Lacy Atkins, The Chronicle

Savannah Fanjul thinks about her step-sister Kayleigh Slusher,...

Image 2 of 4

Roisin Ariaz says a prayer at the memorial for Kayleigh Slusher outside the apartment building, Monday February 3, 2014 where the body of 3-year old little girls body was found dead, Saturday in Napa, Calif. " It's just so sad, she was an innocent," says Ariaz, a retired preschool teacher. The girl's mother Sara Krueger and her boyfriend Ryan Scott Warner have been arrested on suspicion of murder and assault in connection with the killing of Kayleigh.

Photo: Lacy Atkins, The Chronicle

Roisin Ariaz says a prayer at the memorial for Kayleigh Slusher...

Image 3 of 4

This image provided by the Napa Police department shows Sara Krueger, who was detained at a San Francisco Bay Area commuter train station along with Ryan Scott Warner, Sunday Feb. 2, 2014 in the city of El Cerrito, Calif. The couple was wanted for questioning in the death of Krueger's 3-year-old daughter. (AP Photo/Napa Police Department)

Photo: Associated Press

This image provided by the Napa Police department shows Sara...

Image 4 of 4

This image provided by the Napa Police department shows Ryan Scott Warner, who was detained at a San Francisco Bay Area commuter train station along with Sara Krueger Sunday Feb. 2, 2014 in the city of El Cerrito, Calif. The couple was wanted for questioning in the death of Krueger's 3-year-old daughter. (AP Photo/Napa Police Department)

A Napa mother and her boyfriend, who are accused of beating the woman's 3-year-old daughter to death, admitted to police that they hid the child's body in a suitcase inside a freezer for three days, according to court documents released Tuesday.

Sara Krueger, 23, and Ryan Scott Warner, 26, were charged Tuesday with murder in connection with the death of Kayleigh Slusher. Clad in blue jail clothes at an afternoon court appearance, their hands shackled at their waists, they spoke only to confirm their names and to say they couldn't afford a private attorney.

Neither entered a plea. Judge Michael Williams appointed lawyers to represent them and ordered them to return to court Feb. 25. They are being held without bail.

Related Stories

Kayleigh's body was found in her bed Saturday by Napa officers who had been summoned to Krueger's second-floor unit at 2060 Wilkins Ave. to do a welfare check, authorities said. The criminal complaint accuses the couple of killing Kayleigh on Thursday, the day after police had visited the apartment to check on the girl.

Kayleigh had suffered blunt-force trauma and appeared to have been sexually assaulted, said Napa police Lt. Debbie Peecook. The couple were charged with murder and assault on a child resulting in death. Neither faces allegations of sexual assault, though such charges could be added later.

Napa County District Attorney Gary Lieberstein said outside court, "Whether you have children or grandchildren of whatever age, hold them a little tighter tonight."

The couple, who didn't own a car, were spotted leaving the apartment Saturday morning with luggage and were detained the next day by BART police at the El Cerrito del Norte Station. The court documents released Tuesday allege that the couple, after being transferred to the custody of Napa police, confessed to hiding Kayleigh's body.

Police officers had been called several times to the couple's apartment to investigate disturbances, police said. But there had been no calls about Kayleigh, whose father is in prison, to the Napa County agency in charge of protecting children from abuse.

Napa police Capt. Jeff Troendly said Tuesday that officers had been called to the apartment Jan. 27 to investigate a domestic disturbance. The officers confirmed two people had been fighting but made no arrests, he said.

Last Wednesday, Troendly said, someone called and asked police to return to the apartment to check on whether Krueger was using drugs, allowing various people to stay in the unit, and failing to feed her daughter. Officers again did not make any arrests, he said, but confirmed the child was alive and well.